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author | 2022-08-24 18:07:15 +0200 | |
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committer | 2022-08-25 13:51:35 +0100 | |
commit | 4065f0b25b7b30ba4dd4665deb5305ead1c0db25 (patch) | |
tree | 2fd679821962b5181bbfb323b459a873a07d72c9 /sound/soc/apple | |
parent | ASoC: apple: mca: Start new platform driver (diff) | |
download | linux-4065f0b25b7b30ba4dd4665deb5305ead1c0db25.tar.gz linux-4065f0b25b7b30ba4dd4665deb5305ead1c0db25.tar.bz2 linux-4065f0b25b7b30ba4dd4665deb5305ead1c0db25.zip |
ASoC: apple: mca: Add locking
In DAI ops, accesses to the native cluster (of the DAI), and to data of
clusters related to it by a DPCM frontend-backend link, should have
been synchronized by the 'pcm_mutex' lock at ASoC level.
What is not covered are the 'port_driver' accesses on foreign clusters
to which the current cluster has no a priori relation, so fill in
locking for that. (This should only matter in bizarre configurations of
sharing one MCA peripheral between ASoC cards.)
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20220824160715.95779-5-povik+lin@cutebit.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'sound/soc/apple')
-rw-r--r-- | sound/soc/apple/mca.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/sound/soc/apple/mca.c b/sound/soc/apple/mca.c index 807b85469408..aa67d57c9a9b 100644 --- a/sound/soc/apple/mca.c +++ b/sound/soc/apple/mca.c @@ -158,6 +158,9 @@ struct mca_data { struct reset_control *rstc; struct device_link *pd_link; + /* Mutex for accessing port_driver of foreign clusters */ + struct mutex port_mutex; + int nclusters; struct mca_cluster clusters[]; }; @@ -296,16 +299,21 @@ static bool mca_fe_clocks_in_use(struct mca_cluster *cl) struct mca_cluster *be_cl; int stream, i; + mutex_lock(&mca->port_mutex); for (i = 0; i < mca->nclusters; i++) { be_cl = &mca->clusters[i]; if (be_cl->port_driver != cl->no) continue; - for_each_pcm_streams(stream) - if (be_cl->clocks_in_use[stream]) + for_each_pcm_streams(stream) { + if (be_cl->clocks_in_use[stream]) { + mutex_unlock(&mca->port_mutex); return true; + } + } } + mutex_unlock(&mca->port_mutex); return false; } @@ -349,6 +357,11 @@ static int mca_be_hw_free(struct snd_pcm_substream *substream, if (cl->port_driver < 0) return -EINVAL; + /* + * We are operating on a foreign cluster here, but since we + * belong to the same PCM, accesses should have been + * synchronized at ASoC level. + */ fe_cl = &mca->clusters[cl->port_driver]; if (!mca_fe_clocks_in_use(fe_cl)) return 0; /* Nothing to do */ @@ -721,7 +734,9 @@ static int mca_be_startup(struct snd_pcm_substream *substream, cl->base + REG_PORT_CLOCK_SEL); writel_relaxed(PORT_DATA_SEL_TXA(fe_cl->no), cl->base + REG_PORT_DATA_SEL); + mutex_lock(&mca->port_mutex); cl->port_driver = fe_cl->no; + mutex_unlock(&mca->port_mutex); cl->port_started[substream->stream] = true; return 0; @@ -731,6 +746,7 @@ static void mca_be_shutdown(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) { struct mca_cluster *cl = mca_dai_to_cluster(dai); + struct mca_data *mca = cl->host; cl->port_started[substream->stream] = false; @@ -741,7 +757,9 @@ static void mca_be_shutdown(struct snd_pcm_substream *substream, */ writel_relaxed(0, cl->base + REG_PORT_ENABLES); writel_relaxed(0, cl->base + REG_PORT_DATA_SEL); + mutex_lock(&mca->port_mutex); cl->port_driver = -1; + mutex_unlock(&mca->port_mutex); } } @@ -962,6 +980,7 @@ static int apple_mca_probe(struct platform_device *pdev) return -ENOMEM; mca->dev = &pdev->dev; mca->nclusters = nclusters; + mutex_init(&mca->port_mutex); platform_set_drvdata(pdev, mca); clusters = mca->clusters; |